Black and Jewish leaders have formed a coalition to fight hate crimes in response to a rise in the number of hate crime complaints last year that ended with an attack on a group of Jewish students during Chanukah.

Yesterday’s announcement of the coalition comes as elected officials and police seem to be flummoxed by the increasing number of possible bias crimes — in which police have yet to announce that they have caught any suspects.

Hate crime complaints rose as much as 20% last year versus the previous year, even as other crime dropped. Two swastikas were found in Brooklyn last week, on the first two days of 2008.

At Columbia University, the site of several of the more high-profile recent incidents, President Lee Bollinger has said he would stop publicizing any new incidents in an effort to discourage the perpetrators. But the organizer of yesterday’s event, Assemblyman Dov Hikind, suggested that a public show of solidarity by the two main targets of the hate incidents — blacks and Jews — was a better tactic. “We will work together. That’s the message, plain and simple,” he said.

While Mr. Hikind didn’t blame police for not having caught the perpetrators, he suggested the problem was more serious than police have made it out to be. Police hate crimes experts have said that hate crime suspects tend to be young people working alone who commit the incidents as isolated acts.

“I don’t buy any of that,” Mr. Hikind said. “We need to apprehend these people.”